Dominance affects the phenotype derived from an organism’s genes, but it does not affect the way these genes are inherited. Complete dominance occurs when the heterozygote phenotype is indistinguishable from that of the homozygous parent.
Can phenotypes be dominant or recessive?
Recessive alleles only express their phenotype if an organism carries two identical copies of the recessive allele, meaning it is homozygous for the recessive allele. This means that the genotype of an organism with a dominant phenotype may be either homozygous or heterozygous for the dominant allele.
What affects the phenotype?
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal’s genes are expressed, which ultimately affects the animal’s phenotype.
How does incomplete dominance affect phenotype?
Codominance and incomplete dominance yield unique phenotypes for heterozygous offspring (Aa). Incomplete dominance results in heterozygotes with intermediate phenotypes, as in the case of snapdragons when parents with red flowers and white flowers are crossed resulting in heterozygous offspring with pink flowers.
Is there a dominant phenotype?
The genes that are expressed are responsible for your traits, or phenotype. A dominant phenotype is a trait resulting from a dominant gene.
What is an example of phenotype?
Examples of phenotypes include height, wing length, and hair color. Phenotypes also include observable characteristics that can be measured in the laboratory, such as levels of hormones or blood cells.
Do all mutations result in a change in phenotype?
A mutation is a random change in DNA which therefore affects a gene and/or chromosome . Most mutations have no effect on the phenotype. Some influence phenotype to some extent.
Is a roan cow codominance?
In codominance a heterozygous individual expresses both simultaneously without any blending. An example of codominance is the roan cow which has both red hairs and white hairs.